Semi-automatic proximal humeral trabecular bone density assessment tool: technique application and clinical validation.

PURPOSE: This study aimed to apply a newly developed semi-automatic phantom-less QCT (PL-QCT) to measure proximal humerus trabecular bone density based on chest CT and verify its accuracy and precision. METHODS: Subcutaneous fat of the shoulder joint and trapezius muscle were used as calibration references for PL-QCT BMD measurement. A self-developed algorithm based on a convolution map was utilized in PL-QCT for semi-automatic BMD measurements. CT values of ROIs used in PL-QCT measurements were directly used for phantom-based quantitative computed tomography (PB-QCT) BMD assessment. The study included 376 proximal humerus for comparison between PB-QCT and PL-QCT. Two sports medicine doctors measured the proximal humerus with PB-QCT and PL-QCT without knowing each other's results. Among them, 100 proximal humerus were included in the inter-operative and intra-operative BMD measurements for evaluating the repeatability and reproducibility of PL-QCT and PB-QCT. RESULTS: A total of 188 patients with 376 shoulders were involved in this study. The consistency analysis indicated that the average bias between proximal humerus BMDs measured by PB-QCT and PL-QCT was 1.0 mg/cc (agreement range - 9.4 to 11.4; P > 0.05, no significant difference). Regression analysis between PB-QCT and PL-QCT indicated a good correlation (R-square is 0.9723). Short-term repeatability and reproducibility of proximal humerus BMDs measured by PB-QCT (CV: 5.10% and 3.41%) were slightly better than those of PL-QCT (CV: 6.17% and 5.64%). CONCLUSIONS: We evaluated the bone quality of the proximal humeral using chest CT through the semi-automatic PL-QCT system for the first time. Comparison between it and PB-QCT indicated that it could be a reliable shoulder BMD assessment tool with acceptable accuracy and precision. This study developed and verify a semi-automatic PL-QCT for assessment of proximal humeral bone density based on CT to assist in the assessment of proximal humeral osteoporosis and development of individualized treatment plans for shoulders.

Hemiarthroplasty versus reverse shoulder arthroplasty: comparative study of functional and radiological outcomes in the treatment of acute proximal humerus fracture.

PURPOSE: To compare functional and radiographic results of reverse prosthesis versus hemiarthroplasty after complex displaced proximal humeral fractures in elderly patients when adequate ORIF cannot be achieved and prosthetic shoulder replacement is required. METHODS: From 2008 to 2012, 67 patients were treated with hemiarthroplasty or reverse arthroplasty. We evaluated 53 cases with an average follow-up of 27.5 months (range 12-64). Twenty-eight patients with an average age of 71.4 years were treated with a hemiarthroplasty and 25 patients with an average age of 77.3 years with a reverse prosthesis. All patients were assessed before and after surgery by Constant-ASES-DASH score, strength in abduction, ER1, ER2, and X-rays. RESULTS: In hemiarthroplasty group, we observed a mean Constant score of 42.3 pt, ASES score 51.3 pt, and DASH score 46.1, with an average strength of 1.3 lb in abduction and of 3.7 lb in ER1 and 1.8 lb in ER2. In reverse arthroplasty group, we measured a mean Constant of 56.2 pt, ASES 69.3 pt, and DASH score 40.4, with an average strength of 4.3 lb in abduction and of 3.3 lb in ER1 and 3.2 lb in ER2. Radiographically, it is interesting to observe that greater tuberosity healing rate was 37 % in hemiarthroplasty group compared to 84 % in reverse arthroplasty group. About complications, the highest rate was recorded in the hemiarthroplasty group. CONCLUSION: Reverse shoulder arthroplasty indication is steadily increasing in acute displaced proximal humeral fracture. Pain and articular movement results appear better than those with hemiarthroplasty. Our data are similar to the international literature.